Project Summary: Child care is an optimal environment to study influences on children's physical activity (PA) as 74% of US children aged 3-6 years are in child care, and the child-care center (CCC) attended explains 47% of the variance in measured PA, while child age, gender, race, BMI, and parent education combined explains only 3%. The central hypothesis of the application is that children's daily PA is affected by 3 aspects of the child-care environment: its facilities, policies, and staff. Only one published study has examined the effect of child-care policies on PA;none has examined all 3 aspects in concert. The specific aims are to: 1) conduct focus groups and interviews to determine caregivers'beliefs about salient CCC environmental characteristics that could influence children's PA, 2) determine the prevalence and variability of center characteristics thought to be related to children's PA through a telephone survey of all local CCCs and 3) identify the center facilities, policies and staff characteristics that are associated with more time spent in moderate and vigorous PA, while in the center and over the course of a 24-hour day. The 3rd aim will be accomplished through an observational study of 450 children attending 30 local CCCs (15 children per center). Each child will wear an accelerometer (motion sensor) for 24 hours to measure PA. The training objective of this career development award is for the Candidate to become an independent and externally funded investigator in child-care environmental factors related to children's PA and the prevention of childhood obesity. The Candidate's long term goal is to prevent childhood obesity through interventions that increase PA in child care. The training goals are to expand the Candidate's knowledge and skills in 1) environmental determinants of pediatric obesity 2) PA measurement and analysis 3) methods of dietary assessment 4) child-care policies and environment 5) relevant theories of human behavior and environment- al interventions, and 6) advanced epidemiological and biostatistical methods related to clustered design. The mentoring team consists of on- and off-site extramurally-funded researchers with complementary areas of expertise in PA measurement and analysis, built environment and policy assessment, epidemiology of clustered design, and CCC policy and environment. Relevance to Public Health: The proposed work is significant because childhood obesity is a critical health problem, increased PA is a potential solution and offers many other health benefits, and the child care setting offers an opportunity to reach 74% of children at a time-period in which environmental interventions may have a potentially strong and long-lasting impact. The proposed research, coupled with the developmental activities will provide the experience, knowledge, and skills necessary for the Candidate to launch and conduct an independent research career. (End of Abstract)